<style>
    .box{
        position: relative;
        width: 400px;
        border-bottom: 1px solid #ccc;
        margin: 100px auto;
    }
    .box input{
        width: 370px;
        height: 30px;
        border: 0;
        outline: none;
    }
    .box img{
        position:absolute;
        top: 2px;
        right: 2px;
        width: 24px;
    }
</style>
<body>
    <div class="box">
        <label for="">
            <img src="images/close.png" alt="" id="eye">
        </label>
        <input type="password" name="" id="pwd">
    </div>
    <script>
        var eye=document.getElementById('eye')
        var pwd=document.getElementById('pwd')
        var flag=0
        eye.onclick=function(){
        	//点击后 更换文本框类型、图片及标记值
            if(flag==0){
                pwd.type='text'
                eye.src='images/open.png'
                flag=1 
            }else{
                pwd.type='password'
                flag=0
            }
        }
    </script>
</body>
